This subject has come up more than once on the Forums, and opinions are divided. I would say that from your own vast experience without one, you probably don't need one.

I have one, and use it religiously (get down on my knees to plug it in, then pray). A surge protector protects you from exactly ONE surge, then you throw it away and buy another. So, if it never stops a surge, I've wasted my money. If it does stop a surge, I'd rather buy another surge protector than replacement appliances. So, I'm in the "better to have it and not need it, than need it and not have it" camp.

As for type, given its throwaway nature, even if you decide to get one, don't spend big bucks on it unless you're protecting something even more valuable. I got mine at my local Route 66 RV parts store; it's a Progressive Industries SSP-30, regular price $99. I bought mine on sale for a bit less.

I have a background in physics and electrical engineering though these days I write software for a living.

There are two types of surge protectors for RVs that are on the market. The cheap ones are nothing more than a set of MOVs (metal oxide varistors) connected between power and ground. Those will provide some protection against lightning strikes.

The thing is that shore power connections run underground and are generally supplied by pad-mounted transformers which provide enough inherent protection against lightning that any lightning-related surge will, by the time it gets to your trailer, be weak enough that any electronics you might have present can deal with it. Good quality power supplies have their own MOVs or are otherwise designed to deal with voltage spikes.

At one of my last jobs we had a lab where there was a big red power outlet with warning signs on it and a button you could push to apply surges of varying voltages and durations to it. We tested new products on it just to be sure. We also had, on a similar piece of equipment. an insulated wand designed to provide a carefully calibrated 10,000 volt pulse to whatever it touched, and we'd apply it to all exposed connectors and surfaces.

So I would say that the cheap MOV-only surge protectors don't solve any problem RVers actually have, unless you stay in one of the few remaining campgrounds where the shore power comes to the pedestal via overhead wires.

The autotransformer-type surge protectors additionally provide some compensation for slightly low and high voltage. Hughes Autoformer is the best known brand. These will also disconnect power if the voltage is out of specification. They are heavy and expensive.

In general the input voltage range of the autotransformer devices isn't any wider than what the converter and 120v appliances can accept by themselves. In practice the converter, fridge, microwave, and air conditioner will all run fine on any input voltage between around 100 and 135 volts. I know, I've done it.

The autoformer devices will detect and correct certain overvoltage conditions that result from wiring problems in the campground or in the utility equipment serving the campground. These problems are rare.

I don't recommend surge protectors of any type as I think that the weight, hassle, and dollar cost exceeds the value of the protection they provide.

If you're concerned about your electronics, the best thing to do is run all the electronics from the 12 volt system. The converter and 12v batteries provide much better surge protection, for equipment connected to the 12v system, than even the fancy surge protectors provide for the 120v system.

If you're concerned about damaging your converter, consider replacing it with a Xantrex Truecharge, which is designed to run on any voltage from 90-265 and will shut off by itself if the voltage is too low.

RV technicians like to blame air conditioner failures on "power surges" or low voltage. They find it much more convenient than blaming such failures on shoddy design and workmanship on the part of the manufacturer of the air conditioner. Air conditioners have thermal protectors in them which should prevent damage from undervoltage. Again in practice they'll work fine up to 135 volts or so, maybe more.

I don't have a surge protector on my trailer and doubt if I will ever get one.

I have a question for Jammer, I have my trailer plugged into the 125 volt outlet I had installed at my sister's house. When I am in the trailer (2012 27FB) watching a movie off my playstation 3 with a 750 watt heater going sometimes all of the AC outlets shut off. I have checked the shore cord to see if the blue led is on or off because maybe it originated from the house but it is still on. It is always when I draw "too much" power. The outlets usually remain unusable for about 5-10 minutes before they auto-magically come on. No fuses are burned nor breakers tripped in the Converter.
Why would this happen? What is happening, I would love to know what really is happening? I'm I truly using too much power? And should I have it looked at by the dealership? Thanks!

I would start by re-torquing all the connectors in the 120v breaker panel area (with shore power disconnected, of course, for safety). That's usually it. If not you might have a bad cord or a loose connection where the cord attaches to the trailer.

As noted above, there is a lot of difference of opinion in this area... We all have used surge protectors in various applications in our homes, etc, and for the most part, they have never come into play. Call me over-protective, but it just makes sense to us to take this simple precaution ... and we feel it's easier to replace a surge protector if it blows than to replace damaged appliances, etc.

We used to have one of the ~$99 models for our Bambi until one hot day in the summer while running the AC, the female end of the protector and the male end of our shore line decided to overheat and begin to melt. Luckily I noticed it and disconnected them before there was a serious issue...having to replace the male end of the shore line and the surge protector was bad enough. Granted, I am not sure what was going on in that particular situation...it may have been a poor connection or a number of other things, but when I went to replace the surge protector I did more thorough research and realized that the protector we had been using was most likely inadequate for the task and was more suited to pop-ups, etc where there are fewer appliances and electronics aboard...and that a larger, more powerful protector was in order.

We ended up getting a Surge Guard 32730 which is geared to 30-amps and has more protections/features than the one we were previously using. It was not cheap and it is a bit bulky, but I seems worth it to us.

Shortly after we got it we were in a park where we had camped several times. While watching movie one night all of a sudden the power went out. I went to investigate and sure enough, the surge protector had interrupted the current and disconnected our rig from the power source. Curious as to why, I plugged the shore power line into the post outlet and discovered the voltage had dropped significatnly below acceptable ranges. So the surge protector had done one if it's jobs... I reinstalled it and when the current was within acceptable ranges again, it reconnected and we were good to go. We would never have known that this was happening without the protector unless we sat there staring at the voltage meter plugged into an outlet all evening. We have no idea why the voltage dropped, but it happend for 4 nights in a row at this park.

So my money is on making use of a surge protector and taking that extra bit of precaution.

I have and use the same on that TB has. I bought it after I saw the campground host's trailer get nailed by a surge. ??? only effected the power cord?? We found several other outlets in the park damaged also.
My thought is that I carry insurance on the AS for accidents,why not electrical also.
IT ONLY TAKES ONCE.

being a good sam member went to campingworld site and pulled the trigger on the above mentioned surge protector as it was on sale and free shipping. i use them in the home to protect stuff so why not the trailer. we do get lightning strikes as one of my neighbors experienced and i do leave the tt plugged in to the house unless i know when a storm is coming to unplug. now i will have a little more peace of mind at home as well at the campground. thanks for the discussion.

Just a curious question, do these (or any) surge protectors protect from the neutral becoming "hot"? I've had that situation in this house more than once: Tree falls on the power service on the house side of the meter pole. One of the hot wires breaks and then contacts the neutral, which energizes the neutral side of all the appliances in the house, bypassing the ground wire at the breaker box on the house. Most appliances don't like the neutral to be hot. Electric company replaces the appliances. Next storm, tree falls on the power service on the house side of the meter pole.... got the appliances zapped twice, maybe three times. The surge protectors I've seen only protect on the "hot" side...Chain saw all the century old Lombardy Poplar trees that stood after dying for a dozen years, but would come down with a strong South wind.

__________________I admit to being powerless over housecleaning and social niceities Airforums 22655 and now, WBCCI 22655

I would agree with jammer's assessment, if you knew the quality of the wiring you were dealing with. We had some sketchy issues hooking up in Vegas with our pad, and you'd assume with 500 other RV's on site things would be pretty solid... not so.